


get down, down, down

by corsica



Category: Fate/Grand Order
Genre: Blow Jobs, Established Relationship, F/M, Plot What Plot/Porn Without Plot, Semi-Public Sex, Wall Sex, the violence is at the beginning and very brief this is almost entirely a pwp
Language: English
Status: Completed
Published: 2020-12-17
Updated: 2020-12-17
Packaged: 2021-03-11 01:42:37
Rating: Explicit
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 5,118
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28137132
Author URL: https://archiveofourown.org/users/corsica/pseuds/corsica
Summary: A rayshift to Shinjuku goes awry, and Ritsuka's reaction to being saved from danger is...unexpected, though most definitely not unwelcome.
Relationships: Female Fujimaru Ritsuka/Karna | Lancer, Fujimaru Ritsuka/Karna | Lancer of Red
Comments: 6
Kudos: 37





	get down, down, down

**Author's Note:**

> this was my "i'm going to write something under 5k if it kills me" fic. mission failed!
> 
> anyway this was started before santa karna got announced but rest assured i went absolutely batshit over the announcement and am waiting with bated breath for the christmas event to get translated
> 
> this is extremely self indulgent. enjoy.

Ritsuka is about at her wit's end when it comes to Chaldea's rayshifting problems.

Maybe it hadn't been the _best_ idea to only bring one Servant with her to Shinjuku, but it's also asinine that Chaldea's issues with rayshifting never seem to get fixed. She shouldn't have been rayshifted in mid-air, _twice,_ but it still happened, and with things still being finicky _most of the time,_ it means she's now stuck wandering the labyrinthine-like Shinjuku Station on her own while Karna is who _knows_ where trying to find her. At least the bad decision to rayshift while her Command Spells are still in the process of recharging is a bad decision she'd been in complete control over.

And of course communications had been cut off, because God knows she only needs more things to go wrong.

“Sit still and wait” is usually the best strategy in these types of situations, but that had to get tossed to the wayside once she had seen Hornets coming her way, and given how narrow the station is, they wouldn't have had a hard time shooting her down, or at the very least nicking her, and slowly bleeding out in a train station of a grimy Shinjuku much different from the one she'd known is the exact opposite of how she wants to die. So Ritsuka thinks back to all the times she'd played hide and seek as a child and takes that knowledge and applies it to this situation because it's honestly the best she has going for her right now. Attempting to guide Karna to her had been deemed useless by the both of them after two minutes of trying, especially once he had mentioned running into hostiles, so she had left him alone to focus on that while she had spent most her time avoiding the increasing amount of men with guns that were proliferating the station.

_“Have you been able to make contact with Chaldea yet?”_

Ritsuka hears Karna's voice reverberate in her head as she stays crouched down in a shadowed subway tunnel, tapping at the communicator on her wrist impatiently, getting nothing except more frustrated.

_“No. I'm not even getting static. This really can't get much worse.”_

She hears the sound of the safety of a gun clicking off against her head.

This really _could_ get worse. So, so much worse.

 _“Karna, you need to find me,_ now!”

Ritsuka snaps to grab at the gun and point it away from her head, ignoring the ringing in her ears as it goes off, the heat searing her palm and sizzling as her skin burns, a pain her adrenaline makes her disregard as she forces herself to stand up, using most of her strength to both keep the sub-machine gun pointed away from her and to keep his finger on the trigger so the magazine empties completely. The gun clicks, no bullets left, and Ritsuka kicks him in the knee with everything she's got, his grip going just loose enough from the pain that she can yank the gun out of his grip and toss it as hard as she can, as far as she can, into the inky blackness of the tunnel.

The chance to turn tail and flee is cut short by a hand snatching her hair from behind, and she yelps in pain as she's dragged back and slammed into the wall, her vision going starry and two hands start wrapping around her throat. She claws at him, and tries to bring her legs up to kick him away, but it does nothing except serve to piss him off more, and tears prickle at the corners of her eyes as his hands' grip tightens. He is taller and stronger than her and it makes fighting back nearly impossible. The strength she had in her legs drops as it grows harder to breathe.

Her vision is turning spotty. Any air she tries to take in is far too little and she feels herself beginning to slip into the sea of unconsciousness.

She hears a screech, and sees a blur of gold violently collide into the Hornet. The pressure around her neck is gone, but the hands remain, blood dripping out from the ends of his arms before they fall to the ground in a heap of wet flesh. Ritsuka slumps against the wall as she chokes down air, and turns to see Brahmastra's red glint breaking through the void, glowing brighter than she's ever seen before, even as the rest of Karna's face stays encased in shadow. She looks in the other direction, and sees the Hornet pinned to a column several feet away; the sheer force at which he'd been speared through his upper torso had cut through his arms like they had been made out of paper, one end of the spear cracking the pillar and the other protruding out from the spot his bicep should've been. Blood spurts out from the ripped stump, his legs twitching as a red stain seeps out and spreads on his clothes.

His footsteps echo in the long tunnel as he approaches Ritsuka, knocking the detached arms aside with one short sweep of his foot, and as he comes closer, she sees that he is covered in splatters of dried blood—blood that does not belong to him. Though his face is set in the same neutral expression as always, Ritsuka notices just how cold his stare is, and Brahmastra's red gleam is luminous and blinding. His eyes never leave the Hornet still clinging to life as he gently wraps his arm around Ritsuka and cradles her close to his chest.

The Hornet's head jerks, and Brahmastra's high-pitched shriek echoes in the tunnel, its light a focused laser that rips through the darkness, and it turns his head into nothing more than a scorch mark against the tile pillar. His movement stills permanently, and Karna's spear slowly de-materializes, leaving glimmers of gold in its wake.

Brahmastra's shine dulls, little by little, until it at last fades away, and soon Ritsuka is looking up into two blue eyes as his hands cup her face like she is made of porcelain. She blinks at him hazily, and melts into his warm body as he leans down to kiss her. Karna carefully runs a hand up her back to tangle in her hair, and he is mindful of his armor as he embraces her, his face buried in her neck.

“I apologize. I should have gotten here sooner,” her arms shake as she wraps them around his waist, her fingertips brushing against his red cape, “How injured are you?”

“I-I'm okay,” her voice is weak, and he grips her tighter, “It hurts a little to talk...but...it's only that, and my hand...I burned it trying to keep his gun out of my face.”

He pauses, before breaking away from her. Karna's hand trails down to Ritsuka's, fingers wrapping around her wrist as he examines her hand. There is an ugly, red imprint of the muzzle scarred into her palm; his other hand comes up, his thumb lightly stroking against her skin, just grazing against the edge of the mark. The longer he stares at it, the more she can see his eyes narrow, until they close entirely, and his brow pulls into a tight furrow.

“...I'm sorry,” he has a difficult time getting the words out.

“I'll be okay,” she brushes his hair out of his eyes with her left hand before her palm settles against his cheek, and though he meets her gaze, there is still a look of uncertainty on his face, “...You more than made up for it with what you did to that guy.”

“It was a wasteful amount of energy to use on him...but I could not grant him mercy,” he places his hand over her left, “You shouldn't have had to see something so gruesome.”

“I'm used to seeing much worse by now.”

“...While that's true, it doesn't mean you should still be subjected to it,” he removes her hand from his face, and links their fingers together, “I apologize, Ritsuka.”

“Karna, it's fine, I promise. It...it...”

She tucks her face into his chest, his arms holding her tenderly, unknowing of just how flush her cheeks have become as she obscures her face against him.

...It...

...It had been really, _really_ hot.

***

Ritsuka is quiet when they finally return to Chaldea.

He isn't surprised; even after all of her experience in battle, what she went through must've still been something traumatizing to both see and endure. Even outside of the infirmary, where he stands and waits patiently as Mash cleans and bandages her palm—able to hear her fretting over Ritsuka, as well—the responses she gives to whatever Mash is saying are short and distracted.

Karna diligently follows at her side when she is finally, reluctantly, let go, with a promise to Mash that she'll take it easy and change the bandages every day. She reaches for his hand, and he is gentle as he entwines his fingers with hers.

He can feel her squeeze his hand before her walking speeds up, and she turns into a hallway that definitively does not head back to or anywhere near her room, instead leading into one of the many defunct areas in Chaldea still in need of resources being put in to properly restore it. It is confusing, to say the least, but he follows her, turning down the twisting corridors, until they dead-end near a door leading to a custodial closet, a significant distance away from both her room and from the hallway she had originally turned into this area from.

This is...not usual behavior from her, and he looks down at her, eyes slightly narrowed.

“Ritsuka—?”

He's cut off when Ritsuka shoves him up against a wall, hands placed on his chest as she stands on her toes to kiss him breathless. Karna blinks and...goes with it, his fingers curling around her waist as his lips open against hers. Ritsuka moans into his mouth as she presses herself firmly against him, trying to erase whatever space is between them.

When she finally pulls away from him, her face is heavily flushed. He stares at her curiously, and Ritsuka averts her eyes away from him shyly.

“...I liked seeing how protective you got of me earlier. It was...really...” she trails off, and it takes her a moment before she's able to meet his gaze; her lips are slightly parted as she quietly takes in air, and the blush on her face only grows darker as her eyes cloud over.

“...Oh,” he's not sure what else to say, really.

His fingers dig into her waist a little harder as she kisses up his neck, eyes closing as she sucks a mark beneath his jaw.

“Nh...”

She traces the path of his jaw up with her lips.

“Karna...” her voice is hot against his ear; her fingers trace lines down his chest, “Take the rest of your armor off, please...”

He does as asked, breathing in sharply as she grinds herself against him. The way she meets his mouth is sloppy, and he is taken aback by how needy she looks when he pulls away, face flushed and eyes unfocused, fingers splayed out against his chest. Ritsuka's gaze stays focused on his own for a moment before she touches her lips gingerly to his, and Karna's name slips out from her in a whimper as his tongue flicks against her lips until they part for him. He has never heard her make the noises she's making now, desperate and lewd gasps of his name spoken into his mouth as she continuously draws him into her over and over again.

A line of saliva connects them as she pulls back, broken as she follows it to kiss him again—though her pace is calmer and shorter, this time. She is smiling sweetly at him when she breaks to lock eyes with him, for only a moment, before she drops to her knees. Karna can do little more than just stare at her wide-eyed as he feels how fast his pulse hammers away.

Well.

This is.

Certainly new.

While it had definitely been a subject broached in the past, it had always been brought up tentatively, asking if she could “return the favor”, so to speak. He had been acutely aware of how hesitant she had sounded every single time it had been mentioned, and each time it had been easy to talk her down from doing something she had obviously been so nervous about. There had been no bitten lips and twiddled thumbs this time, however; no statements of _“really, I can do it for you, too, Karna”_ that had unmistakable reluctance attached to them. This is the first time he has ever seen her be so...bold.

He blinks. She is not making a move, and it occurs to him that she is waiting for his permission.

The first natural inclination that comes out are the words, “There is...no need for you to do this for me, Ritsuka.”

“I want to, Karna...” she's still smiling at him, “...Is that...okay?”

This had never been something he allowed himself much of in his past life. But the eagerness in her eyes is impossible to miss.

He nods. She lights up.

“Ah...” she hums, “I'm glad...”

“...Ritsu—.”

He's cut off and clamping his hand over his mouth as she gently wraps her lips around him. It is...too much.

Karna has his other hand by his hip, clenched into a tight fist as he forces himself to stay as still as he can, made all the more difficult by just how _enthusiastically_ her tongue is licking against him. He makes a little choked noise as her fingers brush against the back of his hand, and she silently urges him to relax, before placing his palm on top of her head. It sits there, rigid, and it takes him quite a few moments before he cautiously allows himself to relax and sift his fingers through her soft hair.

Though the area _is_ almost entirely abandoned, they are still very much in public and very much could be seen by anyone unlucky enough to wander this way, so he is nearing desperation in his attempts to keep quiet, but Ritsuka seems keen to try and drag out as many pleasured noises as she can from him, moaning as her tongue darts out to lap against him, tasting him, and it begins to dawn on Karna why _she_ reacts the way _she_ does when he has her thighs spread out and held firm in his hands, especially given that she's doing her _absolute_ _best_ to try and get him to break. Her mouth is so warm and—and now she is taking him _even_ _further_ and it is absolutely _everything_ Karna can do at the moment to keep from pushing into that heat.

She finally stops, and her hands rest against his thighs as she exhales through her nose. That is _most_ _definitely_ the back of her throat that he feels, and ironically, he is the one struggling to breathe.

Though he's always run warm, right now, his body truly feels like it's on fire.

At some point, his eyes had closed, something he hadn't even been cognizant of, and he opens them to look down at her, which is a _mistake;_ her face is flushed and her eyes are half-lidded and glassy and she is _meeting his gaze_ and Karna grips her hair tighter as he cuts off the moan that she rips out of him. It is taking every bit of restraint in him to not move. Her tongue runs along the underside of his length and he can feel the intense heat from the flush on his face as he presses his hand harder still against his mouth because that restraint is becoming _increasingly difficult_ to hold onto.

She begins to move her head, and there is a crack in the dam as her name comes out of him in a staggered breath.

“Ri...tsuka...”

She whimpers around him, fingers spreading out against his thighs, and he feels her pull back, tongue grazing against the tip.

_“Nh...”_

She gasps quietly as she removes herself entirely, her fingertips creating shallow divots in his skin.

“Look at me, Karna...”

He...didn't even know he had closed his eyes again, and it takes him a second before he's able to properly respond to her soft and breathy request. He removes his hand from the top of her head, his knuckles stroking along the side of her face before he's cupping her cheek, and she nuzzles against his palm. The blush on her face has only grown darker in shade since he last looked at her, and the color of her lips has changed from a soft pink to a bright, shiny red.

“I don't want you to hold back,” she tilts her head to kiss against his palm, “Okay?”

She grasps at his hand, and it comes off the side of her face as she intertwines their fingers together. His eyes are fixed down on her as her own flutter closed, and she squeezes his hand as she parts her lips around him once more. Karna's breathing is strangled as he watches her take him down inch by inch until he can feel her nose against his pelvis. Keeping himself as still as possible is taking all of his concentration, to the point where he doesn't notice her other hand sliding up his thigh and around to the small of his back. He startles as she pulls him towards her to take him as deeply as she possibly can.

Whatever restraint he still had, crumbles.

Karna clutches her hand tightly in his as he is unable to bite back the quiet, low moan of her name, unable to control his hips as they twitch and push him down her throat, made even harder to control as he can feel that she is _swallowing_ around him. His back hits the wall behind him with a _'thump'_ as he falls against it, and Ritsuka licks her lips as she fully removes herself from him and if _that_ isn't an image he'll have seared permanently in his brain, her eyes all glassy and her cheeks all flushed while she savors how he tastes, staring up at him with such aching affection, softly catching her breath.

His mind is still reeling, playing catch-up as he reaches down to help her up as an automatic response. Ritsuka hums a gentle tune as her fingers run through his hair, brushing it out of his face, and he rests his hands on her waist as he lets her, unable to really do much else at the moment. He is mildly aware of how...debased he must look when she pulls back to get a good view of his face, ostensibly pleased with her work, and she cups his head in her hands. The heat her palms offer is only slightly more than what he is already feeling on his cheeks. In the reflection of her eyes, with his hair no longer blocking his vision, he is able to see the state she has reduced him to.

Her boots crinkle as she stands on her toes. She tips his head down to kiss his forehead, and he leans into her.

“I love you, Karna,” she speaks softly, and the warmth in her eyes matches her words so strongly it is almost more than he can bear. He can feel his heartbeat in his ears, a thundering, pounding drum.

The kiss she presses to his lips is light, and chaste, and the crack in the dam spreads, and spreads, and spreads, until the wall tumbles down entirely.

Ritsuka's breath catches in her throat in a surprised hitch as he kisses her, insistently coaxing her lips open while he pins her between himself and the wall. She wraps her arms around his neck, pulls him into her, gasps into his mouth as she feels his hand slide beneath her tights and press in-between her legs. Her fingers tug at his hair, and she moans loudly, only becoming louder as his middle finger presses in and rubs her through her underwear.

It is a struggle to not simply shred her tights apart, but he sees her kicking off her boots and he's able to keep them from even tearing as he tugs them down and off in one smooth motion. He fumbles with the belts on her uniform, settling for just dropping them on the ground once they're finally off, and he pulls down the zipper to better get at her neck. She whines out his name softly as he sucks against the skin beneath her jaw, and his fingers slip down to push aside her underwear, not even bothering to pull them off, and he raises her leg up high, knee bent, as he pushes into her.

His mind snaps back to him in a rush of panic as he feels her wince, but whatever pain she has passes quickly and in no time at all Ritsuka is whispering his name in a desperate, honeyed tone and she's tugging on his hair and the fog is covering his mind all over again. He reaches for her other leg, hands sliding down to her upper thighs as he holds her up with ease; Ritsuka's skin is so soft and silky that he cannot help but dig his fingertips in. Her heels rest on the small of his back as she crosses her ankles around him, and Ritsuka runs her fingers through his hair and moans as he takes her mouth in his and starts to move. There is no slow build-up, but she is still insistently tugging him further towards her with her legs.

“Karna...” she sighs against his mouth as he pulls back, and before she is able to speak again he slots his lips against hers in a kiss much messier than he used to doing. Ritsuka's breaths are coming out in sharp little bursts as she feels his tongue run along hers; he breaks away for just a moment, licking his lips, before he is rocking into her and kissing her again like a starving man.

His mouth moves to the underside of her jaw, teeth grazing her skin and he can feel the quick, fluttering beat of her pulse vibrating against his lips. He sucks against it until a red spot begins to blossom onto her skin, and nearly pulls all the way out of her before he rolls his hips back inside of her in one quick thrust, and his lips cover hers to muffle the squeal he knew she'd let out.

 _“Ah!”_ her nails rake down his back, “S-So good...you feel so good... _oh...”_ she whines as he licks a long stripe up the side of her neck, then bites into it, “Kar _na...!”_

She is lax around him; it is all she can do to just hold on to him as he kisses her. His teeth catch her bottom lip, and his gaze is predatory as he looks in her eyes, lip slipping out from between his teeth as he pants quietly.

“Ritsuka,” his breath is soft against her lips as he speaks, and she whimpers as he kisses her again, for the briefest of moments, “Say my name like that again.”

She is not given much choice as he sharply rocks back into her.

_“Karna!”_

She cries his name shamelessly and Karna finds himself no longer caring if somebody were to manage to stumble upon them. His hands slowly drag up to the crook of her knees, her legs falling off from around his waist as he hoists them high in the air, nearly folding her in half, and Ritsuka scrambles to pull him closer as she lets off a string of _“yes, yes, yes, yes”_ in time with his pace. The sound of his name is whimpered into his mouth as he kisses her like he is stealing the air from her lungs, latching back on mere seconds after they break apart to nip onto her bottom lip and make it swell more than it already has.

“More, please _please please, Karna, harder, please...!”_

A very small voice in the back of his mind tells him how disappointed and ashamed of himself he should be, because he made her feel like she needed to beg, while a much louder, much more overpowering voice says _“but she sounds so good, doesn't she?”_ and the noises of her needy little pleas head straight south as he obliges her, like he always does, like he always will.

He is positive her nails have drawn blood from how deeply and furiously she has been clawing into his back, but if there is any pain then he certainly can't feel it, too focused on all the sheer warmth her body has to offer as his teeth sink into every inch of her neck that is exposed. The moans that she cries out between sharp gasps for air turn up in pitch and volume as he pulls back slightly to change the angle and the _noises_ she makes, the obscene, desperate mewls that pour out of her as she grinds down against him are just so much _more_ than he's ever heard from her before.

Karna rests his forehead against hers, eyes piercing as he stares at her, but he is caught off guard as Ritsuka clings to him and begins to speak breathlessly.

“I love you, I love you, I love you. I love you. _I love you—.”_

She seems to only be half-aware that she's even talking at all, and Karna cuts her off with a heated kiss...but she is still whispering the words into his mouth, and she says them with such naked, genuine affection in-between every returned kiss that it feels like his heart is going to burst.

Ritsuka's fingers grip onto his shoulders and she is grasping to him for dear life, eyes squeezed shut as his lips press against hers, his tongue licking its way into her mouth and twisting against her own. His hips give a hard roll into her, and Ritsuka's back arches as he hits so _deep,_ her moans nearly incoherent save for the fact that he can just barely make out his name at the tail end of her keening whines.

“K-Karna, I'm so close...” she cracks her eyes open to meet his as she whimpers against his lips, and he lets himself melt into her as they kiss again.

Her arms are wrapped around his neck and she holds onto him as hard as she can, her muscles trembling. Karna can feel how fast her heart is pounding, and he grunts, his breath catching as she clenches around him.

It only takes one more roll of his hips before Ritsuka is crying out and she is so _tight_ around him and he cannot hang on any longer, burying his face in her neck to muffle himself as he spills deep inside of her, hips jerking against her pelvis. Her arms are quivering around his neck, and as the euphoria starts to wear off, as he begins to come back to his senses, he finds himself suitably, horribly embarrassed by just how aggressive he became towards her. Karna kisses the side of her head, above her temple; it is barely an apology, but it's a start, at least.

Carefully, he slowly eases her legs down to the ground, and she shivers as her bare feet hit against the cold tile. His armor gleams as it materializes over his body once more. There is...nothing he can clean her with, so he settles for dressing her and fixing her clothes as best he can.

As he puts in the last belt on her shirt, he steps back, and takes her in. She is leaned back against the wall, catching her breath; her legs are shaking, her lips are shiny with spit, her cheeks have red blossoming on them, and he pauses for a minute as he realizes that this is the first time he has been able to bring her to this state without using his fingers. All it took...was...

He closes his eyes and a light flush appears over his face. This is not something he will take pride in, given how badly he lost control of his wits.

“Karna?” her voice is quiet as she finally speaks, large eyes bleary and blinking up at him, “Are you alright?”

His eyes open, and he watches she she presses her hand flat against the red gem in his chest.

“...I should not have acted the way I did. I'm sorry,” he can feel his face heat up, and Ritsuka laughs softly.

“Hm? But I liked it. A lot,” her other hand comes up to his chest.

“...I see,” his voice is strained.

Ritsuka hums, and slides her hands up until she's cupping his face, “Would you do it again sometime if I said I wanted you to?”

The answer is undoubtedly _yes,_ but he _really_ doesn't want to say that, so he keeps quiet as he tries to figure out a way to respond that isn't quite so damning.

His hesitation is noticed, and the corner of Ritsuka's lips twitch up into a wry smile, “Or...am I going to have to get on my knees every time I want you to act like this?”

He chokes on nothing, sending him into a short coughing fit. Ritsuka's smile only gets wider.

“I guess that wouldn't be so bad. I did all that work training my gag reflex, after all.”

“You did—.”

Karna can't finish speaking, and Ritsuka watches gleefully as his face heats up more. He places his hand over his mouth and his eyes squeeze shut. Ritsuka laughs gently and reaches up to take his hand off of his face. She links their fingers together, standing on her tiptoes to kiss his cheek.

“Sorry. You're fun to tease, and I don't get the chance to do it that often,” she squeezes his hands, “I love you, Karna.”

He takes a deep breath, “You are the most important person to me, Ritsuka. For as long as you want me to stay by your side, I'll be there.”

“I know,” she pauses, “I'm serious though, I really did train my gag reflex.”

“...Yes. I could tell. You made it...abundantly clear.”

**Author's Note:**

> i know that what happened to the hornet is not how human bodies work but please understand that i both a) wanted to write karna yeeting his lance and b) wanted to write a guy getting his arms ripped off
> 
> anyway i cannot wait til 2022 when i can have santa karna and make him throw hands with everyone like he was truly meant to do while also hopefully getting vritra and having a dedicated milf join the team


End file.
